Composite elements, in particular insulated tubes

摘要

Composite elements, comprising a foam (i) on the basis of polyisocyanate - polyaddition products of the isocyanate structures and comprises on the reaction of (a) isocyanates with (b) compounds reactive toward isocyanates is based, characterized in that, as (b) at least one compound having a hydroxyl number of less than 120 mg of koh / g is present.